How to Read Resistance Values using Analog Multitester

Summary

This instructional video teaches how to use an analog multi-tester to measure resistance values. It covers the calibration process, the use of different resistance multipliers, and how to interpret the readings. The video demonstrates measuring a carbon resistor's resistance, adjusting the tester's multiplier, and reading the ohm values. It also explains how to identify short circuits and open circuits, emphasizing the tool's importance in diagnosing electrical issues.

Takeaways

• 🔍 An analog multi-tester can measure resistance, current, and voltage values.
• 📏 To measure resistance, select the appropriate resistance multiplier (1, 10, 100, 1k, 10k, etc.).
• 🔧 Before measuring, calibrate the multi-tester by connecting the positive and negative probes until the pointer reads zero.
• ⚙️ If the pointer doesn't point to zero, adjust it using the ohm adjuster.
• 🔄 If the resistance value is too high, switch to a higher multiplier to get a more detailed reading.
• 📊 To read the resistance value, count the lines on the scale corresponding to the selected multiplier.
• 🔢 The final resistance value is calculated by multiplying the scale reading by the selected multiplier.
• 💡 A carbon resistor was used in the example, and its resistance was found to be approximately 560 ohms.
• 🌐 For a more precise reading, use a higher multiplier and recalibrate the tester accordingly.
• 🚨 A reading of zero ohms indicates a short circuit, while infinite resistance suggests an open circuit.
• 🔦 The multi-tester is a useful tool for diagnosing issues in circuits, such as shorts or open circuits.

Q & A

What are the three parameters that can be measured using an analog multimeter?

The three parameters that can be measured using an analog multimeter are resistance values, current, and voltage values.

How do you calibrate an analog multimeter before measuring resistance?

To calibrate an analog multimeter before measuring resistance, you connect the positive and negative probe. It is necessary that the pointer points at the zero value. If not, you adjust it using the ohm adjuster.

What are the resistance multipliers available on the multimeter?

The resistance multipliers available on the multimeter are 1, 10, 100, 1k, 10k, and 100k.

Why might the needle not move when measuring resistance with the multimeter set to a certain multiplier?

The needle might not move when measuring resistance because the selected multiplier is too low, indicating that the resistance value of the resistor might be higher than the range of the selected multiplier.

How do you read the resistance value on an analog multimeter?

To read the resistance value, you look at the position of the needle on the scale. You count the lines from zero to where the needle points and multiply by the selected multiplier to get the resistance value in ohms.

What does it mean if the multimeter's needle points to a high value when measuring a resistor?

If the multimeter's needle points to a high value when measuring a resistor, it indicates that the resistance is low, and a higher multiplier should be selected to get a more accurate reading.

How do you determine the appropriate multiplier for measuring a resistor's resistance?

You determine the appropriate multiplier by starting with a lower multiplier and observing the needle's movement. If the needle does not move significantly, you increase the multiplier until you get a clear and accurate reading.

What is the significance of the zero ohm reading on an analog multimeter?

A zero ohm reading on an analog multimeter indicates a short circuit, meaning there is no resistance between the points where the test probes are connected.

What does an infinite resistance value signify on an analog multimeter?

An infinite resistance value on an analog multimeter signifies an open circuit, meaning there is no continuity between the points where the test probes are connected.

How can you use a multimeter to check for defects in circuitry or wiring?

You can use a multimeter to check for defects in circuitry or wiring by measuring the resistance. If the resistance is zero, it may indicate a short circuit. If the resistance is infinite, it may indicate an open circuit.

What is the next step after measuring resistance with an analog multimeter?

The next steps after measuring resistance with an analog multimeter, as mentioned in the script, would be to learn how to measure current and voltage, which will be covered in subsequent videos.

Outlines

00:00

🔍 Measuring Resistance with an Analog Multimeter

This paragraph explains how to use an analog multimeter to measure resistance values. It covers the selection of appropriate resistance multipliers (1, 10, 100, 1k, 1000, 10k) and the calibration process required before measurement. The speaker demonstrates how to adjust the multimeter's ohm adjuster to ensure the needle points to zero. They then proceed to measure a carbon resistor's resistance, starting with a low multiplier and increasing it until the needle moves significantly. The process of reading the multimeter's scale to determine the resistance value is explained, including how to mentally divide the scale for precise readings. The speaker concludes by measuring a resistor and explaining how to calculate the actual resistance value by multiplying the scale reading by the selected multiplier.

05:01

🔌 Understanding Multimeter Readings and Resistance Calibration

The second paragraph delves into the process of using different multipliers (1k, 10, 1) for measuring resistance with an analog multimeter. It emphasizes the need for recalibration after changing multipliers to ensure accurate readings. The speaker illustrates how to interpret the multimeter's scale for resistance values, explaining that each line on the scale represents a unit increase in resistance. They demonstrate measuring a resistor and converting the scale reading into ohms by multiplying by the selected multiplier. The paragraph also discusses how to identify short circuits and open circuits using the multimeter, highlighting the importance of resistance measurement in diagnosing electrical issues. The speaker concludes by encouraging viewers to watch upcoming videos on measuring current and voltage.

Keywords

💡Analog Multi-tester

An analog multi-tester is a device used to measure various electrical parameters such as resistance, current, and voltage. In the video, it is the primary tool used to demonstrate how to measure resistance values. The script explains how to calibrate and use the multi-tester with different multipliers to get accurate readings.

💡Resistance Values

Resistance values refer to the opposition to the flow of electric current in a circuit. The video focuses on measuring these values using an analog multi-tester. It is a fundamental concept in electronics, and the script provides a practical demonstration of how to measure it using the multi-tester.

💡Calibration

Calibration is the process of adjusting a measuring instrument to ensure its accuracy. In the context of the video, the analog multi-tester must be calibrated by connecting its positive and negative probes and adjusting it until the pointer points to zero, which signifies that the device is ready to provide accurate measurements.

💡Multipliers

Multipliers are settings on the analog multi-tester that adjust the range of the measurements it can take. The script mentions multipliers such as 1, 10, 100, 1k, 1000, and 10k ohms. They are crucial for measuring resistance values accurately, as different resistors have different resistance levels that require the appropriate multiplier for precise readings.

💡Ohm Adjuster

The ohm adjuster is a knob on the analog multi-tester used to adjust the scale to zero before taking a measurement. The script describes how to use the ohm adjuster to calibrate the device, which is an essential step to ensure that the readings are accurate.

💡Carbon Resistor

A carbon resistor is a type of resistor that uses carbon as the resistive element. In the video, the script mentions measuring the resistance value of a carbon resistor as an example. It is a common component in electronic circuits and understanding how to measure its resistance is important for troubleshooting and building circuits.

💡Short Circuit

A short circuit occurs when an unintended low-resistance path in a circuit bypasses one or more components. The script explains that if the multi-tester shows zero ohms when the probes are connected, it indicates a short circuit, which is a fault condition that can damage electronic devices.

💡Open Circuit

An open circuit is a break or discontinuity in a circuit that prevents current from flowing. The script mentions that if the multi-tester shows infinite resistance, it indicates an open circuit, which also prevents the proper functioning of electronic devices.

💡Kilo Ohms

Kilo ohms is a unit of electrical resistance equal to one thousand ohms. The script uses this term when explaining how to interpret the readings from the analog multi-tester. For example, if the pointer is on the 13 mark with a 1k multiplier, the resistance is 13 kilo ohms.

💡LED

LED stands for Light Emitting Diode, a semiconductor device that emits light when current flows through it. In the script, an LED is used as an example to demonstrate how the multi-tester can be used to check for continuity, which is a crucial test for ensuring that components like LEDs are functioning correctly.

Highlights

Three parameters can be measured using an analog multi-tester: resistance values, current, and voltage.

Today's focus is on measuring resistance values and learning to read the analog multi-tester.

Available resistance multipliers include 1, 10, 100, 1k, 1000, 10k.

Calibration of the multi-tester is necessary before measuring resistance values.

The pointer should point at zero value for accurate calibration.

Adjustment of the ohm adjuster is required if the pointer is not at zero.

If the ohm adjuster is at maximum limit, adjust the needle manually.

Use the multiplier one to measure resistance values.

No movement of the needle indicates a need for a higher multiplier.

Switch the multiplier to 10 for higher resistance values.

Calibrate the tester again when changing the multiplier.

Reading the resistance value involves mentally dividing the lines on the scale.

The value of the resistor is calculated by multiplying the scale reading by the multiplier.

For example, a reading of 13 on a 1k multiplier is 13 kilo ohms.

LEDs can also be tested for resistance using the multi-tester.

A reading of zero ohms indicates a short circuit.

An infinite resistance value signifies an open circuit.

The multi-tester is a useful tool for diagnosing defects in circuitry or wiring.

Stay tuned for upcoming videos on measuring current and voltage.

Transcripts

[Music]

there are three parameters that we can

measure using an

analog multi-tester so these are

resistance values

current and voltage values

so today we're going to measure

resistance values first

and also i'm going to teach you how to

read the values

on the analog multi-tester so since

we're going to measure the resistance

values

you could be able to use any of these

resistance multipliers so we have here

multiplier 1

multiplier 10 100 1k

or 1000 and 10 000 or 10k

so before we measure the resistance

value

we have to calibrate first the

multi-tester

by simply connecting the positive and

the negative proof

so it is necessary that the pointer

points at the zero value

since the pointer is not on the zero

value

we have to adjust it using the

ohm adjuster but unfortunately it is

already on its maximum limit

so we'll try to

adjust the needle

there it goes okay and then we're using

the multiplier one

so let's say for example i'm going to

measure the resistance value

of this resistor assuming also that i'm

clueless

on the resistance value of this resistor

what i'm going to do is that measure the

value

using the multiplier one and then

connecting my test probes in parallel

with the

resistor by the way this is a carbon

resistor

so as you can see

there is no movement on the needle

it doesn't mean that it has no values

it's just

that

the multiplier is too

low perhaps the value of this resistance

is high

so what we're going to do is that we're

going to switch

the multiplier to 10.

apparently the needle moves a little so

i want a more detailed value of

my tester so

what i'm going to do is that i'll move

my tester when i try to adjust

my tester or my knob into

100 multiplier then i have to calibrate

first

by adjusting the

ohmic knob

until such time that the needle points

to zero

so since that the needle points already

to zero then

it means that we could measure now the

resistance value

using the multiplier of 100

so again we're going to see

resistance value you have here

zero one two three five

and then this is your five units

this is your 10 it's up to you to divide

the line

mentally you can mentally divide

the the lines or count the lines of the

omic value the value of this

um resistor is

6 ohms 6 ohms then you have here the

multiplier 100 that will become

6 times 100 it is equivalent to 600

ohms volume of this resistor is 560 ohms

but based on our reading

of course we cannot read the exact

560 ohms

if there's not much discrepancy or

difference with the value

it's okay so let's try another

resistor

supposedly i would like to move

to 1k

okay i make use of the multiplier 1k

i can also make use of multiplier 10

multiplier one but let's say for example

i make is of multiplier 1k

so again since i adjust the tester

i have to calibrate it and then

adjust the knob until such time that it

reaches the zero

okay so there it goes so it's already on

the zero ohms

then release then we have to measure the

resistance value of this this is store

okay so to be able for me to demonstrate

the display i'll fold the terminals

okay okay so

as you can see

the pointer points

on the on this point

on this area will read the values

on the uppermost scale

because this is where the resistance

values

place in so

0 1 2 3 4 5

10. and then this is your 10

this is your 20 so you'll try to divide

each line to be able for you to reach

20 from 10 each line

will be represented by

unit of one let's try one two three

four five six seven eight nine ten

so there are ten lines of each

line each small line will be represented

by unit 1

10 11 12 13.

so this is 13 ohms

but you have a multiplier 1k

okay so 13 times 1k

that is 13 k ohms

or 13 000 ohms

but in engineering we made use

of the three zeros as

represented by kilo so that will become

13 kilo ohms

13 times 1k is 13

k ohms okay so let's move now to this

led so let's try

moving your tester to

again calibrate your tester

okay the needle points to zero so

there's

no need of calibrating your tester

the short terminal is for the positive

of your test probe the longer terminal

is for

your negative test probe

the needle is on the

20 value here

so 20 times 100 that is

2 kilo ohms

so 20 times 100 that is 2 000

ohms or 2 kilo ohms

so that will become two kilo ohms

normally if it's zero ohms it means that

the circuit is shorted

so let's say example we tried to connect

the test probes positive and negative

you can see that the needle fluctuates

to the zero ohmic value

this means that it is short circuit

but if you try to disconnect

the resistance is

an infinite value which means this is a

very very high resistance

and therefore the circuit will be open

open circuit so resistance is a very

useful tool for determining if the

circuit is shorted or

open if there is a defect on your

circuitry

or even in your wirings if there is a

short head or an open circuit

so that's all for now please watch my

next videos

for the current and voltage

measurement

thank you and god bless